四、后端数据处理（C#代码示例）

// 使用阿里云数据库RDS进行数据查询
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        BindNewsData();
    }
}

private void BindNewsData()
{
    // 通过阿里云SDK获取数据库连接字符串
    string connectionString = AliyunSDK.GetRdsConnectionString("NewsDB");
    
    using (SqlConnection conn = new SqlConnection(connectionString))
    {
        string query = @"SELECT Id,Title,Summary,ThumbnailUrl,PublishDate,IsHot 
                        FROM News WHERE Status=1 ORDER BY PublishDate DESC";
        SqlDataAdapter da = new SqlDataAdapter(query, conn);
        DataTable dt = new DataTable();
        da.Fill(dt);
        
        PagedDataSource pds = new PagedDataSource();
        pds.DataSource = dt.DefaultView;
        pds.AllowPaging = true;
        pds.PageSize = dpNews.PageSize;
        
        rptNews.DataSource = pds;
        rptNews.DataBind();
    }
}

protected void rptNews_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || 
        e.Item.ItemType == ListItemType.AlternatingItem)
    {
        DataRowView row = (DataRowView)e.Item.DataItem;
        Label lblHot = (Label)e.Item.FindControl("lblHot");
        lblHot.Visible = Convert.ToBoolean(row["IsHot"]);
        
        Image imgThumbnail = (Image)e.Item.FindControl("imgThumbnail");
        string ossUrl = "https://oss.aliyun.com/bucket/" + row["ThumbnailUrl"];
        imgThumbnail.ImageUrl = string.IsNullOrEmpty(row["ThumbnailUrl"].ToString()) ? 
            "/images/default-thumb.jpg" : ossUrl;
    }
}

public string TruncateContent(string content, int length)
{
    return content.Length > length ? 
        content.Substring(0, length) + "..." : content;
}